1. Field of the Invention
The present invention relates to energy absorbing systems, and particularly to a modular wall system which can be installed on existing concrete barrier walls in order to absorb the energy from a vehicular impact.
2. Description of Related Art
There are a number of injuries and fatalities every year due to collisions between vehicles and concrete barrier walls. This problem is especially prevalent in racing situations where drivers can reach speeds in excess of two hundred miles per hour and tracks are completely surrounded by concrete barrier walls. Concrete barriers walls are effective in keeping vehicles on the track, but impacts with these barriers can cause serious injuries or death to the drivers of the impacting vehicles due to the unyielding nature of concrete. Many of these injuries could be avoided if more impact energy was absorbed by the barrier wall rather than the occupants of the vehicle. It is therefore desirable to have an effective energy absorption system which is cost effective and easy to install on existing concrete barrier walls.
There have been a variety of systems proposed to reduce injuries to drivers when vehicles accidentally impact concrete barriers. One system is the PEDS barrier which employs high density polyethylene barrels connected to the concrete barriers with longitudinally spaced cables extending around the barrels. The barrels themselves are wrapped in a overlapping sheet of high density polyethylene material which is attached to the barrels by bolts. This system is effective in reducing injuries and absorbing energy but it is costly to install, difficult to repair and does not use air as an energy absorption means.
U.S. Pat. No. 6,276,667 discloses an energy dissipating system which is attachable to concrete barriers. This system consists of a horizontally extending flexible sheet of plastic secured to the barrier so as to form a cavity between the barrier and the plastic sheet. Inside this cavity is an elongated energy dissipating member extending horizontally within the cavity. This system is designed to reduce friction between vehicles and the barrier, but it is not designed to absorb the energy of a head-on collision at racing speeds. This system also does not have a slide-on, slide-off design, and does not use air as an energy absorption means.
U.S. Pat. No. 6,010,275 discloses an impact attenuating guard rail and includes a rail extending horizontally, a plurality of fixed support posts and a resilient, compressible, energy absorbing means mounted between the rail and the posts. This is an effective energy absorbing system but the guard rail does not use air as a means for dissipating crash energy, nor does it easily attach to an existing concrete barrier wall.
U.S. Pat. No. 5,314,261 discloses a vehicle crash cushion which includes an array of panels positioned to overlap one another and which is oriented parallel to a barrier adjacent to a roadway. Located between the panels and the barrier are elastomeric tubes which function to absorb energy when the panels are depressed toward the barrier. This system differs from the present invention in that it does not use air to dissipate crash energy. It also lacks a slidable connection to a concrete barrier wall for easy installation and repair, and it is not designed to reduce debris associated with impact. The elastomeric tubes are open at top and bottom so that they collapse readily against the barrier wall, whereas the present invention uses a unitary, enclosed core with restricted orifices venting to the atmosphere, so that considerably more force is required to compress the core of the present invention. The elastomeric tubes described in Stephens are bolted to each other, requiring considerable labor to assemble, and are secured to the concrete barrier by bolting only a single tube to the barrier. Further, the front panel is made from plywood wrapped by fiberglass, so that the plywood is prone to fracture on high speed impact. The front panel is secured to the concrete panel by a complex suspension cable structure, and apparently is not attached to the elastomeric tubes.
There is a need for an improved energy absorbing system, which is easier to install and replace, does not retain water after a rain storm which might otherwise cause a dangerous track condition, uses air as an energy absorbing means, and is designed to repeatedly absorb an impact and contribute little if any debris to the race track.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.
The soft wall for race tracks is an energy absorption system for absorbing vehicular impact energy in order to reduce injuries. The invention is a modular system having a plurality of laminated panel structures adapted for attachment to concrete barrier walls. The panel structures are slidably attached to brackets mounted to the concrete barrier wall. Each panel structure consists of an elongated, flat, front panel, a flexible core layer, and an elongated, flat, rear panel. The core layer resembles a wall and has a front, back, top, bottom, and left and right sides. The rear panel is flush with the back of the core layer, but the front panel is offset from the front of the core layer so that the adjacent structures overlap. The core layer is hollow and when viewed from above is shaped like a parallelogram. Vertically extending partition walls support the core layer internally and divide the core layer into a plurality of vertically extending parallelogram shaped chambers. Each chamber contains several apertures so that adjacent chambers are in fluid communication with each other and the atmosphere, thus allowing air in the chambers to escape to adjacent chambers or to the atmosphere when the chambers are compressed upon impact. The soft wall has several feet attached to the bottom of the core layer to assist in drainage.
Accordingly, it is a principal object of the invention to protect race car drivers from injury in crashes by reducing the rate of negative G""s on the driver.
It is another object of the invention to provide an energy absorption system that can easily be affixed to or removed from a track wall.
It is a further object of the invention to provide an energy absorption system which will not retain water between itself and the track which could seep out later and provide a dangerous track condition.
Still another object of the invention is to provide an energy absorption system having impact resistant plastic panels to reduce the incidence of fracture when struck by a vehicle, thereby reducing accident debris which might otherwise delay a race with additional clean up time, while still providing a cushion for the barrier, and so that the integrity of the soft wall is not compromised by collision whereby the wall does not have to be replaced after every impact.
It is an object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.